Drifting-valve for locomotives.



0. BIGELOW.

DRIFTING-VALVE FOR LOCOMOTIVES.

APPLICATION FILED JULY 27. l9l4.

1,206,982. Puma Dec. 11916.

OWEN BIGELOW, F MOMENCE, ILLINOIS.

DRIFTING-VALVE FOR LOCOMOTIVES.

Specification of Letters Patent.

Patented Dec. 5, 1916..

Application filed July 27, 191i. Serial no. 853,485.

T 0 all whom it may concern:

Be it known that I, OWEN Brennow, a citizen of the United States, residing at Momence, in the county of Kankakec and a State of Illinois, have invented new and useful Improvements in Drifting-Valves for Locomotives, of which the following is a full, clear, and exact description.

My invention relates to drifting valves for locomotives, and particularly to the valve connected to the steam-chest of the cylinder of "the locomotive to automatically regulate the pressure of the steam within the cylinder as the speed of the locomotive gradually decreases to the stopping point.

The obiect of my invention is principally utilize thevacu em-caused by the recipro- 1 cation of the piston after the steam has been.

cut oil' to automatically operate the valve to permit the ingress of a limited amount of live steam in diminishing quantities as the speed of the locomotive decreases to the stopping point at which point the valve automatically closes the inlet ports of the drifting valve in which position said drifting valve will remain, and owing to the steam pressure within the steam-chest will keep said inlet ports closed when the engine is started again and while it continues in operation. This I accomplish by the means hereinafter fully described, and as particularly pointed out in the claims. I

In the drawings: Figure 1 is a diagrammatical view of a locomotive showing the application of my improved valve thereto. -Fig. 2 is an enlarged horizontal section through my improved drifting-valve Referring to the drawings, A represents a locomotive of a conventional type; B the cylinder thereof and C the steam-chest or steam passage-way. communicating with the cylinder. -The cylinder and the part connected therewith through which the live steam .passes in transit from the boiler to the cylinder to reciprocate the piston, and which I have termed a steam-chest, may be constructed in any of the numerous ways in which the are now constructed, and my improved drlft-valve may be connected to any part of the steam-chest or its equivalent passage-way of the same. Besides communicating with the steam-chest of steam passage-way the housing 1) of my improved so long as it communicateswith the steam.

valve is connected. to the dome a of the boiler b of the locomotive by a suitably disposed valve-controlled pipe 0.

The cast metal housing comprises a stepped cylindrical portion about onc third of the length of which constitutes a seat (Z for the valve, hereinafter referred to, and is greater in diameter than the remainderthereof which constitutes the seat 6 in which the stem of said valve is reciprocable. The side-wall of said housing bulges laterally away from the inner side of said cylindrical portion toward the steam-chest to form a chamber E, which latter communicates with the interior of said steam-chest through the port 7. This chamber E incloses the inner side of the cylindrical portion of the valve and is open to and conununicates with the open end of the valve-seat (Z thereof: through an opening y in the inner segment of the same next the end wall of the housing and communicates with the opposite open end of the stem-seat e of the cylinder, through opening 7: in the inner segment thereof.

, The larger seat (Z oi the cylinder is, preferably, about onehalf as long as the smaller seat e of the same, and is in axial alinen'iont therewith, and. a floating-valve and its stem are seated in and reciprocable in the same. Head K of this valve comprises a circular disk and occupies the bore of the end of the cylinder having the greatest diameter,

and a vent a; is, preferably, made in the shoulder between the enlarged portion and the reduced portion of the cylinder to permit of the gradual exhaust of the air in the chamber back of the said head. in the larger seat al of the cylinder, or the gradual in-- crease of the air thereto, according to the movement of said head. The stem 1. of said floating valve extends in axial alinement with said head into the reduced bore of seat e, which is lined with a suitable bushing it its entire length, substantially as shown in the drawings. The periphery of the valve head-K is provided with. suitable packing a and the central portion of its outer side next the removable cylinder head L is built out or protrudes. so as to hold it away from said head and leave a space between. them. The stem I of this valve is of such a length that when the valve-head is in the position. shown in Fig. 2 of the drawings, it extends into the bore of seat 6 a distance, preferably the head, said seat is provided with an annular chamber M, and the bushing it is provided with a circumferentially disposed series of perforations to permit communication between said bore and said annular chamber, which latter has a screw-threaded opening N extending therefrom into which the pipe that connects the housing of my drifting-valve with the dome is screwed.

The operation of my improved driftingvalve is as follows: WVhen the steam is shut 01? from the cylinder, the reciprocablemovement' of the piston creates a vacuum in the passage-way through the steam-chest or its equivalent. This vacuum acting upon the outer sideof head K causes the valve to move into the position, substantially as shown in Fig. 2 of'the drawings, and the stem of the valve moving therewith uncovers the perforations connecting the annular chamber M and the bore of the seat a of the cylinder and permits steam from pipe 0 to enter the said bore and chamber E to overcome the vacuum. The moment, however, that the steam from pipe 0 creates a condition of pressure in chamber E and the steam-chest or its equivalent, or the moment the steam is turned into the steamchest, or its equivalent, and fills the passageway leading to the drive cylinders to start the locomotive, the steam pressure engages the outer surface of valve-head K, which, owing to its area being greater than the opposite end of the stem I, moves said valve and .its stem away from cylinder-head L and the stem closes the perforations leading t6 the annular chamber M and shuts ofi the steam from pipe 0.

incense What I claim as new is:

1. In a locomotive boiler, a drifting-valve comprising a suitablehousing, a portion of which is formed into a cylinder one end of which is less in diameter than the. other and connecting the annular chamber to the boiler the bore of the discharge end of which is less than said discharge port, and a solid piston the head of which is reciprocable in the enlarged end of said cylinder and the stem of which is reoiprocable in the smaller end of the cylinder and regulates the ingross of steam from said annular chamber.

2. Ina locomotiveboiler, a drifting-valve comprising a Suitable housing having a horizontal cylindrical upper chamber which enlarges at one end, and a lower steam chamber which communicates with the opposite ends of the cylindrical upper chamber, and a reciprocating valve and its stem mounted in the cylindrical upper chamber.

3. In a locomotive boiler, a drifting-valve comprising a solid reciprocating valve and its stem, a suitable housing having a stepped cylindrical portion about a third of the length of which constitutes a chamber for the valve and is greater in diameter than the remainder thereof which latter constitutes a chamber in which the stem of said valve is reciprocable, and the side-wall of said housing being bulged laterally away from the lower part of the cylindrical portion to form a lower chamber which communicates respectively with the. opposite ends of the chambers in the cylindrical portion.

In witness whereof I have hereunto set my hand this 17th day of July, 1914;.

owen BIGELOW. I

Witnesses:

FRANK D; THoMAsoN, FLORENCE MITCHELL. 

